The invention is based on a method for adjusting an annular gas gap for metering the gas, of a device for injecting a fuel-gas mixture. German Offenlegungsschrift 32 40 554 already discloses a device for injecting a fuel-gas mixture, which relates to a fuel injection valve having a gas guide sleeve surrounding the valve end of the fuel injection valve. A narrow annular gas gap is formed between one end of the valve and the gas guide sleeve and serves to meter the delivered gas, striking the fuel, and communicates with an annular gas conduit. Adjusting the quantity of gas delivered by the annular gas conduit and thus adapting the annular gas conduit to the requirements of the engine and to various types of injection valves is possible in this device only by displacing or bending the gas guide sleeve. This expensive method for adjusting the device entails high production costs, in large-scale mass production.